


Keith Finds a New Toy

by ilovelocust



Category: Voltron: Legendary Defender
Genre: Alien Sex Toy, Anal Sex, Bottom Shiro (Voltron), M/M, Sounding, Stuffing Shiro Full of Alien Goo, bottom!shiro
Language: English
Status: Completed
Published: 2017-03-28
Updated: 2017-03-28
Packaged: 2018-10-12 07:53:06
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,856
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10485927
Author URL: https://archiveofourown.org/users/ilovelocust/pseuds/ilovelocust
Summary: Keith finds out what kind of sex toys a race of alien shape shifters uses.  Of course, he has to try it out on Shiro.





	

**Author's Note:**

> I got stranded on the side of the road, without my notes for Mirror Mirror, so I wrote this instead.

Keith finding the jelly was a complete accident. He had just happened to stumble upon Coran explaining to Pidge what exactly the piece of Altean technology she had found was for, and rescued it before she could incinerate it and all its instructions.

In what really shouldn’t be a surprise, a race of shape shifters generally expected their fun time toys to have the same capabilities. The jelly was one such toy. In it’s dormant state it was approximately a two gallon crystal clear goo that held a perfect drop shape. It’s exterior covered in a slippery substance not unlike lube. Slap the the control band on his wrist, though, and it could move and take any shape that Keith could think of. Literally, it ran on mental commands from its user.

A crash course through every instructional manual and piece of porn using the thing he could find, along with some personal test runs on himself, and Keith was ready to try it with a partner. Lucky him, he had a boyfriend willing to experiment.

-

As Keith watches the jelly slide up Shiro's cock, from where he’s positioned between Shiro’s legs, he thanks every life decision that has led to this moment. It was all worth it, the thing works exactly as advertised. A thought and the jelly increases the pressure around Shiro’s half hard dick. 

“Oh, that’s different.” Shiro says, interested but not blown away.

Keith snorts at him, “Give me a moment,” He says, “How about this.” He tells the jelly to create low and high pressure waves running up and down his cock. That makes Shiro choke on his words. “See told you it was like nothing you ever felt.” Keith may be preening a bit, but he was now winning their unofficial competition on who can keep it most interesting in the bedroom, “Now lay back and enjoy. You aren’t doing anything tonight.” Keith gives Shiro a little shove, so he plops back on the mattress with a chuckle. Recovered from his initial surprise apparently. Keith would have to work on that.

Keith tries a couple different things to see what gets the best reaction. Alternating high and low pressure along the whole cock at once, making swirls of pressure that move around in circles, and even concentrating on the head and balls. The last one combined with the waves seems to be what Shiro likes the most. It doesn’t take much of that for Shiro to grow fully hard. Absolutely leaking, as a matter of fact, precum drifting out like smoke into the goo surrounding it. 

Shiro’s dick is standing tall and proud inside the jelly now, so Keith pulls the thing down to rest around his balls. Exposing Shiro to the cold air. The older man lets out a frustrated noise at the abandonment. Keith feels a little bad, but there is an obvious next step and he doesn’t want Shiro to cum before he’s had a chance to experience it, “Knees up, baby. I want to see it fuck you.” Keith cajoles. Shiro obliges, pulling his knees up to give a slightly better angle. On a whim Keith tells the jelly to lift Shiro’s hips up a bit and is pleasantly surprised when it succeeds. “You ready?” Keith asks.

“As I’ll ever be,” Shiro responds, still out of breath from his cock being played with.

The first strand of jelly is no larger than a pencil, but it has difficulty wiggling past the ring of muscles guarding Shiro’s hole. Keith isn’t surprised. He loves his boyfriend to death, but he’s a bit of a tight ass. Getting him to obey orders is easy. The old Garrison Golden Boy lives to snap-to to an authoritative voice, but he’s wound so tight, getting him to physically relax is a production. Good thing Keith has a production planned.

A little more pressure and Shiro’s muscles part. The strand of jelly quickly snakes deeper. Now comes the fun part, the jelly is one continuous mass. Keith doesn’t need to force anything else in. He just orders the strand to swell, and it grows inside Shiro. Getting thicker and thicker at Keith’s will. He lets it get as wide as one of his fingers before he pauses and tells it to search along Shiro’s inner walls. He’s done this with his physical hands before, so it doesn’t take him long to make Shiro buck as he finds his prostate.

“Good?” Keith asks. When Shiro opens his mouth to respond Keith has the jelly press up again, ripping a moan from him instead. It’s worth the irritable swat Shiro aims at him a moment later.

“Brat,” Shiro grumbles at him.

Keith lets the strand start swelling again and has it start to pulsate against the spot. Shiro throws his head back against the bed, “You know you love me,” Keith teases.

“That’s-ah-cheating,” Shiro gasps. Shiro looks delectable like this. Eyes clenched shut, lips parted as he moans. Keith indulges.

Bracing his hands on either side of the larger man’s chest, Keith leans forward and captures Shiro’s mouth with his own. Shiro tastes a bit too much like the overly minty Altean toothpaste they are all forced to use, but the kiss is sloppy and wet just like he likes it. When Shiro’s hands leaves the sheets to yank Keith flat against him, it qualifies as just about perfect.

He breaks it off before they can both start rutting against each other. His own dick is painfully hard, and he knows he’d let all his plans go to waste if they got started. 

While he was distracting Keith, Shiro’s hole has swallowed more and more of the jelly. When he sits back on his haunches, Keith’s pleased to see that it’s swelled to at least the size of his own dick. Letting Keith have a tantalizing view of his insides.

Shiro’s ass may be getting close to where he wants it, but Keith isn’t done with him yet. He has another hole he wants to fill before they are done. The jelly surges up to envelop Shiro’s cock. This time it doesn’t stop at just covering the outside of Shiro’s dick. Once it swallows up the head, it begins to press into his slit and the urethra beyond. “Keith!” Shiro spasms and cries out at the sensation.

“Shhhhh,” Keith hushes him, rubbing a calming hand up and down Shiro’s calf, pulling the jelly back a bit, “It’s okay, baby. I’m in control. This will make you feel good.” Shiro relaxes back into the bed at Keith’s words, just surprised not injured, “Just let me know if anything hurts and I’ll ease off.”

“Alright,” Shiro nods.

“Good boy,” Keith whispers, kissing the top of one Shiro’s knees.

Shiro calmed, the jelly presses back in. This time Shiro only gasps as it pushes deeper. The jelly is so much better than normal sounding tools. Shiro can twitch and buck all he wants and the soft jelly won’t go a centimeter further in than Keith wants it to, and right now Keith wants it to go deep, past Shiro’s balls and even further in. He briefly toys with the idea of trying to find Shiro’s prostate from this end. He knows it can be done, but the insides of his urethra was delicate and Keith didn’t want to ruin the evening by applying too much pressure. He’d just have to settle for letting the jelly fuck Shiro’s cock like this. He orders it to go in deep almost almost to his bladder, just to pull out to the very tip before slowly pushing back in again.

Shiro arches and makes the most gorgeous whining sounds of pleasure as the jelly continues its twin points assault. The bits of it pressed inside Shiro’s dick rolls in time, deeper and shallower, with the waves of pressure on the outside. Both running in counterpoint to the knot of force inside him expanding and deflating against his walls, stimulating his prostate. He was a beautiful shivering mess. Keith felt like he could come just from watching him like this.

A thought and the jelly put Shiro on display for Keith, holding his cheeks apart so Keith could get a good view of where his twitching hole was accommodating the jelly’s clear mass. Keith could see inside him. See through the jelly to where Shiro’s wet pink walls were forced open. He could stick two of his fingers into Shiro right now, as deep as they would go, and they’d never touch the sides of Shiro’s hole. Keith fisted his hand around his own leaking cock.

Maybe he'd fuck Shiro like this. Fuck right into his open needy hole and let the jelly squish and squelch along his insides as Keith took him. Smooshing it against his walls and deeper inside him with each thrust. Use his dick to pack it into him. Filling Shiro's intestines up until his tight little stomach started to swell. He wouldn't even need a plug to keep it all in once Keith was done. He could just will it to stay put and all Shiro's muscles couldn't squeeze it back out again.

He'd take Shiro to the bathroom and show him his swollen stomach in the mirror. Let him see how much he'd taken in. Then he'd make him watch himself while he got him off. He'd whisper in Shiro's ear about how good he'd been while it squirmed inside him. Pump him until he screamed Keith's name in release. Only then would he remove it from inside Shiro. Slide it out of his loose hole, let it drip down his legs to the floor. Shiro would watch that too. Leaning heavily on Keith for support, but eyes never leaving the mess between his thighs.

Shiro shouts, whole body straining off the bed and going still as he comes, then he collapses back down. Keith pulls the jelly back from Shiro’s over-sensitive cock, stops the pulsing inside him, but he leaves his ass stuffed open. Uses Shiro’s post orgasm relaxation to force it even wider for his own viewing pleasure, as he strokes himself. He’s so close it only takes him a little bit to follow Shiro over the edge. Letting his cum spurt into the jelly to float with Shiro’s own.

Keith collapses down beside Shiro. Trying to catch his breath. He finds his hands drifting down Shiro’s abs to the jelly still between his legs. He should remove it completely now that they are done, and he does reduce the size, so Shiro isn’t quite so stretched. Yet, as his fingers press through the jelly to touch the ring of Shiro’s still open hole, he finds that he really likes the idea of leaving him like this. His insides, exposed and ready if Keith feels like doing anything else to him later in the night. It was really fucking hot, and if he hadn’t just come the idea alone would be more than enough to get him ready for another round. 

Well, Shiro hadn’t complained so far. Leaving the jelly a little longer couldn’t hurt.

**Author's Note:**

> Remember how the Zelda fandom used to have pictures of Link having sex with those Jelly monsters (can you tell I've never played the games). That idea always stuck with me, and is a big a part of what inspired this fic. I hope you enjoy reading it as much as I did imagining it.
> 
>  
> 
> Also, if you have any idea of what this kink is actually called please tell me. I tried to properly tag everything, but I really have no clue.


End file.
